Mercedes-Benz Bus History - Daimler

of nearly 30,000 over a long career spanning 16 years – more than
any bus before it.
On December 6, 1954, St. Nicholas’ Day, the first O 321 H came off
the production line in Mannheim, the plant that not long before had
been declared the central bus plant of Daimler-Benz AG. Its semi-
integral design was a major departure from the conventional chassis
construction and, with the exception of the major drive assemblies,
removed all similarities in design between buses and trucks once and
for all. Just a few years earlier, the Mercedes-Benz O 6600 H had
heralded this development, with its forward-control cab position and
rear-mounted engine. Its body, however, had been built on an entirely
conventional ladder-type chassis.
The backbone of the O 321 H on the other hand was a frame/floor
assembly designed to be self-supporting. The body was then welded
firmly to this high-strength frame. Together these two components
resulted in an extremely rigid body shell, lending the overall design
higher stability, lower weight and – with the removal of the chassis
side members – a larger luggage compartment between the two axles.
Coil springs on the front axle instead of the leaf springs used hitherto
served to improve ride comfort. The O 321 H heralded a new era in
Mercedes-Benz bus design.
At the same time, the separate frame/floor assembly of the new bus
permitted the company to continue supplying conventional
bodybuilders with the chassis. And coachbuilders in Germany and
elsewhere gladly availed themselves of the opportunity to create
individual body designs for buses of every conceivable kind.
Nevertheless, as a complete vehicle with three-pointed star, the
original Mercedes-Benz O 321 H was pleasing enough to the eye in its
Daimler Communications, 70546 Stuttgart/Germany
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